Arbitrary Logic

We’re continuing to modify the glide:

from glider import *


def query():
    contracts = Contracts().with_name("ERC721").exec(10)
    return contracts

This time, we’re going to add more logic to it besides the initial request to the DB.

contracts variable contains List[Contract], remember? What we can do is loop through the contracts, as was mentioned in Get Started, getting some properties.

Modifications

To begin with, let’s add an additional variable between the two other instructions and change the return statement to this variable:

from glider import *


def query():
    contracts = Contracts().with_name("ERC721").exec(10)

    result = []

    return result

We will save the properties there.

Next, we’ll add a for loop, which will append contracts to the result variable:

from glider import *


def query():
    contracts = Contracts().with_name("ERC721").exec(10)

    result = []
    for contract in contracts:
        result.append(contract)

    return result

This doesn’t make much sense at the moment because the result of this glide is identical to the one without these modifications :D

Anyway, now we have individual access to every Contract instance from our DB request. What can we do with it? Let’s check the Contract API documentation… Contract.events() looks promising.

Add the method call:

from glider import *


def query():
    contracts = Contracts().with_name("ERC721").exec(10)

    result = []
    for contract in contracts:
        result.append(contract.events())

    return result

And hit the run button!

Oops, an error :) TypeError: Object of type Event is not JSON serializable means we’re trying to put something wrong to the output.

As you can see in the documentation, the method returns List[Event] type. I’ll spare your time and tell that if we try to output one Event it’ll lead to an error again. And this means we must:

Save the events to a new variable.
Loop through again.
Call one of the Event properties or methods (docs) to get any serializable value, like .name.
Change the return statement using the trick from Get Started

from glider import *


def query():
    contracts = Contracts().with_name("ERC721").exec(10)

    result = []
    for contract in contracts:
        events = contract.events()

        for event in events:
            result.append(event.name)

    return [{"result": result}]

And our beautiful glide is done! It’ll output all the event names from the first ten contracts in the DB with the “ERC721” name:

Result

Modifications#

Modifications